Question

A person invested some amount at the rate of 12% simple interestand some other amount at the rate of 10% simple interest. He received yearly interest of Rs 130. But if he had interchanged the amounts invested, he would have received Rs 4 moreas interest. How much amount did he invest at different rates?

Class 10

Content Quality Solution Required

No Spamming otherwise reported on the spot

Answer 1

HELLO. !!!....


_____________________


●Let the amount invested Rs x at the rate of 12% and Rs. y at the rate of 10%

According to the question :-

●simple intrest on Rs x at 12%  + simple intrest on Rs. y at 10% = 130 

we know simple intrest = (principle ×  rate × time )/100 and apply the formula

(x × 12 ×  1)/100 + ( y ×  10 ×  1)/100 = 130

=> 12x + 10y = 13000  ......................( equation 1)

●If he interchanged the amount invested , he would have received 4 more on intrest 

then ,

simple intrest on Rs x at 10% + simple intrest on Rs. y at 12 % = 130 + 4

( x ×  10 ×  1)/100 + ( y ×  12 ×  1)/100 = 134 

=> 10x + 12y = 13400  ................................( equation 2)

●solving  both equation we will multiply by 12 in (equation 1) and multiply by 10 in (equation 2)

144x + 120y = 156000

100x + 120y = 134000

-  -  -  ( subtracting the equation)

44x = 22000

x = 500 

● put the value of x = 500 in equation 1 

12 ×  500 + 10y = 13000

6000 +10y = 13000

10y = 13000 -6000

10y = 7000

y = 7000/10

y = 700

●the amount invested at 12 % is 500 Rs and 10 % is 700

●we use simple intrest formula SI = (P × R × T) /100 

●and the value is x = 500 Rs 

 y = 700 Rs.

_________________________

HOPE IT HELPS U DEAR !!!!

HAVE A GOOD SLEEP :))

# NIKKY

Answer 2

Heya......✋
Your answer is in attachment.....